How to name or rename your iPhone, iPad, or Apple Watch

Our devices come with us everywhere — don't they deserve a name to call their own? Whether you like creative naming or you just want a unique moniker for your iPhone, iPad, or Apple Watch, here's how to do it.

Fun fact: You can use emoji to name your devices. Do with this information as you please.

Thanks. I've tried all this and it already shows up with my new assigned name under settings.
But when I emailed something to myself (a video) it still showed up under the original name. Any ideas why and what I should do?